Answers: What Dry Food Does to Your Cat's Fur
Last Updated on Saturday, January 09, 2016 10:08 PM
Published on Saturday, January 09, 2016 10:04 PM
Written by Guillermo Díaz, MV
My cat is a two year old, short-hair tabby and he excessively sheds all of the time. I took him to the vet and after several tests the doctor says he is completely normal. This is bittersweet to me because I'm happy he's a healthy cat, but worried that he sheds so much. He is eating only a premium brand of dry food the vet recommended. Why does he shed so much?
I think this is one of the most common questions vets get asked about in daily practice. The process by which cats change or renew their coat is called shedding and is a continuous and natural process in a cat's life. Shedding is mainly influenced by sunlight or photoperiod, which is the number of hours a cat is exposed to the sun in a day, hormones, genetics and nutrition. Outdoor cats may lose more hair in the spring and fall and retain more fur in the winter, while indoor cats can shed all year round because of the artificial light and generalized use of air conditioning and heating, both of which trick the cat's system and often lead to continual, rather than seasonal, shedding.
A healthy, well-fed cat should generally shed very little. When plucking the fur with the index finger and thumb you should get very few loose hairs compared to the bunch or clump of hairs caught when the shedding is excessive or pathologic. Normally, the coat should look smooth and shiny with no visible patches of bald skin, no thin or matted areas and no offensive smell. You should consider making an appointment to get your kitty checked by the vet if your cat obsessively licks, bites or scratches or if he's losing patches of hair. There are a variety of medical, dietary and stress-related issues that can cause your cat to lose more hair than normal. At the vet's office, the doctor must consider different conditions which may be causing excessive shedding. The most common are:
- Parasites, such as fleas
- Fungi/yeast infections
- Bacterial infections
- Granulomas, which are nodules that may be caused by infections
- Hormone imbalances, such as hyperthyroidism and Cushing's disease
- Some kinds of tumors
- Excessive bathing/shampoo
- Pregnancy and/or lactation
The doctor will perform several tests in order to diagnose the condition of the cat. These may include:
- Blood work to assess the general condition of the patient, detect infections and to check hormone status, i.e. the thyroid gland.
- Culture/sensitivity to detect the exact pathogen and which drug will effectively eradicate the infection.
- Skin scrapes, for detecting parasites such as mites.
- Allergy skin testing.
Now, it happens very often that after a thorough medical examination everything is okay, as happened to the person writing the question of this topic. There is no infection of the skin, the hormone levels are within normal limits, there are no mites or fleas causing problems and no detectible allergies. What to do then, when, according to the medical protocol, everything has been ruled out? What is missing?
When everything has been ruled out you must consider the food. A quick review of the ingredients of commercial dry foods reveals these important facts:
- Poor quality protein: too high in vegetal protein content compared to animal protein content.
- Poor quality fat: the fat added to the mixture is cooked at high temperatures, denaturing it and altering its biological properties.
- Biological value of the proteins is decreased by extreme temperatures.
- Carbohydrate content is too high: at least 40 to 45 percent of the weight of the bag is carbohydrate. This can include ingredients such as corn meal, corn gluten meal, brewer's rice, ground whole wheat and soy flour meal. These ingredients have no business in a strict carnivore's diet, nor do they contribute to the protein synthesis necessary for hair growth. Remember that the normal carbohydrate content of a cat's natural prey diet is around 1 to 5percent, no more.
Keep in mind that the "bricks" that build every single hair of a cat are the amino acids
, which come from the breakdown of the proteins the cat ingests. These proteins are meant to be from an animal source. Not all proteins work the same way. Gluten is a vegetal protein derived from wheat that is widely used in the cat food industry to boost measured protein levels. It's used because it is cheap. Cats, being strict carnivores, lack specific enzymatic pathways and cannot utilize plant proteins as efficiently as animal proteins. In other words, the quality of the bricks are deficient to build hair, therefore the quality of hair produced will be deficient as well. Besides all of the above, proteins are heat sensitive and the extrusion process used to make dry kibble
foods requires very high temperatures, altering or destroying the biological value of the protein. The fat that is added during the process is also altered due to the extreme temperatures. Preservatives have to be added to the food to keep the fats from becoming rancid.
The proteins found in raw meat have a complete amino acid profile that matches perfectly with the cell receptors in the cat's body, which allows them to work efficiently to form healthy skin and hair cells. When cats begin eating a raw meat diet, the change in the skin and coat is just amazing. Generally, people begin to see substantial improvement in their cat's coat in a few weeks, including softer fur, elimination or reduction in dandruff and much less shedding.
Note: Feline Nutrition provides feline health and nutrition information as a public service. Diagnosis and treatment of specific conditions should always be in consultation with your own veterinarian. Feline Nutrition disclaims all warranties and liability related to the veterinary advice and information provided on this site.
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Dr. Guillermo Díaz studied veterinary medicine at the Universidad Mayor de San Marcos in Lima, Perú. He currently practices in Lima and also provides veterinary services to a large number of local rescue organizations.